Purpose :
To elucidate the role of biopsy and histologic grade on patient outcomes for ocular surface squamous neoplasia (OSSN) with involvement of multiple ocular structures (clinically stage T3).

Methods :
A Retrospective chart review of patients undergoing treatment for OSSN at the USC Roski Eye Institute for OSSN identified 27 cases demonstrating clinical involvement of multiple ocular structures without orbital invasion. Tumor characteristics were evaluated by slit lamp photography and AS-OCT images. Size, and location were documented. Lesions involving any of adjacent structures were considered stage T3, according to the definitions provided by the AJCC, 7th edition. Primary surgical versus topical chemotherapy treatment was determined by the ocular oncologists. Biopsy was done in 17 patients. Histologic grade, treatment modality, time to cure, disease recurrence and/or persistence were documented for each neoplasm.

Results :
Of the 27 cases 12 were treated primarily with surgery and 5 with chemotherapy. Among the 17 biopsied tumors, 11 demonstrated invasion beyond the basement membrane, classified by the AJCC 8 Ed. as stage T3. The remaining six neoplasms were staged as Tis based on lack of basement membrane invasion despite diffuse clinical involvement. There was no significant difference in persistent disease or recurrence, or time to cure when T3 and Tis tumors that received the same initial treatment were compared (excised T3 versus excised Tis; medically-treated T3 versus medically-treated Tis; p > 0.5 for all comparisons).

Conclusions :
Clinical diagnosis of stage T3 OSSN based on involvement of multiple sites as described in the AJCC 7th ed. criteria was not predictive of basement membrane invasion in our cohort of biopsied OSSN lesions. While biopsy is a requirement for grading based on AJCC 8th Ed there was no significant difference in time to cure, persistent disease or recurrence between stage T3 versus Tis. Thus, although the current staging guidelines require biopsy, we found that this did not significantly affect patient outcomes.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.